as in treacherous
formal
causing harm in a way that is gradual or not easily noticed
Most people with this insidious disease have no idea that they are infected. an insidious enemy
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Recent Examples of insidious
Through that longtime relationship and writing Caddy for Life about Edwards, who died from ALS in 2004, Feinstein became dedicated to fighting the insidious disease — including donating half the profits of the book that became one of his 23 to land on The New York Times bestseller list.
—
Vahe Gregorian, Kansas City Star, 26 Mar. 2025
But the insidious nature of the illness rendered those efforts fruitless.
—Orlando Sentinel and Virginian Pilot Editorial Boards, The Orlando Sentinel, 26 Mar. 2025
In a hybrid world, where our online and offline lives are increasingly interwoven, the erosion of agency can manifest in insidious ways.
—Cornelia C. Walther, Forbes, 22 Mar. 2025
So parties like Germany’s AfD and Hungary’s Fidesz developed an insidious three-step maneuver:
Boldly and loudly champion Israel and its right-wing prime minister, Benjamin Netanyahu, to create pro-Jewish bona fides.
—Zack Beauchamp, Vox, 19 Mar. 2025
See All Example Sentences for insidious
Vahe Gregorian, Kansas City Star, 26 Mar. 2025
But the insidious nature of the illness rendered those efforts fruitless.
—Orlando Sentinel and Virginian Pilot Editorial Boards, The Orlando Sentinel, 26 Mar. 2025
In a hybrid world, where our online and offline lives are increasingly interwoven, the erosion of agency can manifest in insidious ways.
—Cornelia C. Walther, Forbes, 22 Mar. 2025
So parties like Germany’s AfD and Hungary’s Fidesz developed an insidious three-step maneuver:
Boldly and loudly champion Israel and its right-wing prime minister, Benjamin Netanyahu, to create pro-Jewish bona fides.
—Zack Beauchamp, Vox, 19 Mar. 2025
See All Example Sentences for insidious
Recent Examples of Synonyms for insidious
Adjective
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Their stories are full of danger: treacherous rivers, unforgiving terrain, and the constant threat of violence and exploitation.—
Alan Taylor,
The Atlantic,
27 Mar. 2025
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But in between lies a tense and treacherous journey…In Wolof and French with English subtitles.—
Ut Community Press,
San Diego Union-Tribune,
25 Mar. 2025
Adjective
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Mulaney’s approach to social commentary on his show is even more subtle; sometimes, concentrating a sketch on a character like Willy Loman is enough.—
David Sims,
The Atlantic,
7 Apr. 2025
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The game is a fun but challenging exercise for your brain which asks players to group words based on subtle and sometimes tricky connections, which tests your logic and language skills.—
John W. Dean,
MSNBC Newsweek,
7 Apr. 2025
Adjective
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But the jitters still shook him, a false-start whistle blowing on his first 40-yard attempt at February’s NFL combine.—
Luca Evans,
Denver Post,
13 Apr. 2025
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Sanchez and her co-conspirators created false documents for the victims, including Permanent Residence cards and Social Security cards, and helped the victims find employment in the Hartford area.—
Stephen Underwood,
Hartford Courant,
12 Apr. 2025
Adjective
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The Federal Trade Commission works to ensure the advertising Americans see is not deceptive, and the Securities and Exchange Commission makes sure that the companies people invest in are not making false claims about their financial prospects.—
Joseph P. Tomain,
The Conversation,
27 Feb. 2025
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The Federal Trade Commission (FTC) has taken some steps to regulate the collection of data in vehicles, focusing on consumer protection and preventing deceptive practices.—
Eric Reicin,
Forbes,
26 Feb. 2025
Adjective
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Jake Gyllenhaal is his foil as the perfidious Iago, who goads Othello into unreasoning jealousy with lies about his beloved Desdemona (Molly Osborne).—
New York Times,
New York Times,
17 Feb. 2025
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Since then, Putin has sought instead to rally the public to the defense of a motherland besieged by the perfidious and cunning West.—
Leon Aron,
The Atlantic,
5 Dec. 2024
Adjective
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Hallucinations, on the other hand, occur when an AI system is asked to provide factual information or perform specific tasks but instead generates incorrect or misleading content while presenting it as accurate.—
Anna Choi,
The Conversation,
21 Mar. 2025
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With large language models – the underlying technology of AI chatbots – hallucinations are pieces of information that sound convincing but are incorrect, made up or irrelevant.—
Anna Choi,
The Conversation,
21 Mar. 2025
Adjective
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His interrogator conceded that the police must have gotten the wrong guy and released him within weeks.—
Gisela Salim-Peyer,
The Atlantic,
10 Apr. 2025
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Five justices said the lawsuit was brought in the wrong venue.—
Devin Dwyer,
ABC News,
10 Apr. 2025
Cite this Entry
“Insidious.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/insidious. Accessed 17 Apr. 2025.
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